The Science of Dieting and the Jupiter Scientific Dieting Method
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The Science of Dieting


This report analyzes dieting from several scientific viewpoints. From this information, we produce one of the most effective approaches to weight reduction. Those readers, who wish to skip the scientific analysis and go directly to the weight loss program, should click here and also review the case studies below..

The Anthropology of Dieting

Before the agricultural revolution 10,000 years ago, Homo sapiens were gatherer hunters: They searched for and ate wild fruits, nuts and vegetables, and they killed animals for meat. Obtaining enough food was a question of life and death. It was possible for ancient modern humans to die of starvation 10,000 to 200,000 years ago, particularly in bad climatic times, be they frigid conditions or extensive droughts. For this reason, “evolution has created” within the human body a desire for food and, in particular, food with high caloric content. Those Homo sapienswho formed a fat reserve in goods time were able to survive the badtimes. And those who didn't died. Such evolutionary (dietary) developments change slowly, so that, although food is abundant today, there is still a strong instinctive urge to eat.

The Biology of Dieting

The biological consequence of this evolutionary effect is simple: (Fact A) When a person eats food, almost every calorie is extracted from it (except for people with certain metabolic diseases or dysfunctions). If the body cannot immediately use the calories, then the calories are stored. The main storage locations are: the liver, the muscle cells and adipose tissue. The liver stores glucose, the muscles store glucose and fat nearby for immediate energy needs, and adipose tissue is the storage region for fat.
     The body uses calories for its energy needs, such as for muscle movement (~28%) including the pumping of the heart, for the thinking, processing and messaging in the brain (~20%), for the functioning of other internal organs (~33%), and for other miscellaneous body parts such as bone, skin, intestines and glands (~20%), where the percentages in parentheses correspond to fractional amounts consumed in the restive state. The brain can only use glucose (carbohydrates) as its energy source except when starvation sets in. For this reason, the human body has a tendency to crave for carbohydrates including sugar.
     (Fact B) When the energy needs of the body are less than the calories obtained through eating and the liver cannot store any more calories, then the calories are converted into fat cells independently of whether the excess calories are in the form of carbohydrates, fat, or proteins. Therefore, in terms of dieting, the number of calories consumed is the thing that matters most; the type of diet (be it low-fat, low-carbohydrate, high-protein, etc.) is of secondary importance.
     The body is designed not to overeat, at least on a short-term basis. Hence when the stomach is full, hormones are produced that reduce the desire for food. The stomach is a muscle, and as such can expand when a lot of food is consumed and can contract when empty. The latter can help in dieting because an empty “contracted” stomach requires less food to feel full.

The Physics of Dieting

The conservation of energy is one of the fundamental principles of nature. It applies to everything including humans:

Energy gained by a body = Energy in - Energy out           (1)

Because of Facts A and B above, almost every food calorie (which is a unit of energy equal to 4184 Joules) that enters the body is stored or used. Hence, Energy out is well approximated by the energy used in exercising and in performing biological functions; little is lost as “waste” (Fetal matter contains very few calories.) Since Energy in is the energy contained in food, Equation (1) becomes

Energy gained by a body = Energy in food eaten - Biological energy expenditure           (2)

     Conservation of mass is another principle of physics. It affects short-term but not long-term body weight. If a person eats a pound a food, the body weight increases by a pound. However, whether that pound is maintained by the body is determined by the caloric content of the food. If a person eats a pound of roughage with (almost) no calories then it will pass through the body and later be defecated as a pound of waste thereby leading to no long-term weight change. Similarly, drinking a liter of water will cause an immediate one-kilogram increase in body weight but will later be disposed of through perspiration, exhalation or urination; no long-term weight increase will occur. In short, because of the evolutionary effects on eating, the body focuses on retaining energy and not mass. As a consequence, when it comes to dieting, it is the conservation of energy and not mass that counts!

The Chemistry of Dieting

When a person eats more than necessary, the left-hand side of Equation (2) is positive, and the human body will use the excess energy to create fat primarily consisting of triglycerides. The chemical reaction is:

glycerol + fatty acid1 + fatty acid2 + fatty acid3 → triglyceride + water      .

     As is evident from this equation, a triglycerides is comprised of three fatty acids. If the body needs to use the energy from fat reserves, the triglycerides are broken down into fatty acids via the opposite chemical reaction

triglyceride + water → glycerol + fatty acid1 + fatty acid2 + fatty acid3      .

and then the fat acids are oxidized to supply the body with energy. Compared to other molecules, fats are very efficient in storing calories for future use.

The Mathematics of Dieting

If the left-hand side of Equation (2) is positive for an extended period, a person will gain weight. On the contrary, if the left-hand side of Equation (2) is negative for an extended period, a person will lose weight as the body uses the energy in fat cells for its biological needs.
     Equation (2) does not depend on the nature of the energy source, only on the amount of calories entering a human body. On a long-term time scale, when the left-hand side of Equation (2) is non-zero, the gain or loss becomes the gain or loss of fat. The number of calories stored in a fat cell (and in the fat of food in general) is 9 calories per gram. Hence,

Weight gained (in grams) = (Calories in food eatenBiological energy expenditure)/9           (3)

The calories per gram in other types of food sources are less:
     Energy in 1 gram of carbohydrates = 4 calories
     Energy in 1 gram of protein = 4 calories
In addition, the energy in alcohol is 7 calories per gram, (which is the scientific origin of the “beer belly”).
     From the above analysis, one comes to the following important conclusion

     The Fundamental Principle of Weight Loss: To lose weight, one must create a daily caloric deficit and maintain it over a period of time.

     Since the daily caloric deficit is (Biological energy expenditure Calories in food eaten), one must either eat less, exercise more, or do both to lose weight, a fact that is very well known. However, this section on The Mathematics of Dieting allows one to quantify this statement.
      Suppose for example, that a person could create a caloric deficit of 180 calories per day. Then, Equation (3) tells us that the person will lose 180/9 grams or 20 grams per day. In 50 days, a person would lose a kilogram or about 2.2 pounds.

The Psychology of Dieting

It is important not to confuse the long-term change in body weight due to a daily caloric deficit or surplus with short-term weight changes. Short-term weight changes are due to eating, drinking, sweating, urinating and defecating as explained in the last paragraph on conservation of mass in the section entitled The Physics of Dieting above. Indeed, it takes considerable time to get fat removed from the body.
     Hence, the person who claims to have lost 5 pounds in one week has probably lost the weight because of a temporary lack of food and water in the body. To lose 5 pounds of fat, a person would have to create a caloric deficit of over 20,000 calories! It is not uncommon for a professional soccer player to lose 5 pounds in a match; however, almost all that loss is in sweat, and will be regained through the drinking of fluids within a day or two.
     Short term weight changes (which are due to conservation of mass and not of energy) can play havoc with the mind of the dieter. If a person sees a sudden weight drop, then he or she is likely to be delighted with the results, only to find that the weight is regained a week later. If a person sees a sudden weight increase, then he or she can become depressed.
     Losing weight requires determination. So one should adopt this mind frame: one should become a determined person. It is also helpful to develop a new attitude toward food; it should be regarded as something necessary for biology survival. It should not be regarded as a source of pleasure. So if one is serious about dieting, it may be worth making food palatable but not excessively delicious.
     Another problem with diets is the weight rebound. This occurs when a person has targeted and obtained a substantial weight loss. The person then resorts to old eating and life style habits, only to find that the weight is regained over a period of months. When a person has successfully dieted and ceases wanting to lose more weight, it is very likely that an adjustment to the diet is needed, that is, some dieting will still be required to maintain the lower weight.

The Jupiter Scientific Approach to Weight Reduction

Jupiter Scientific's path to weight loss is a modification of one's eating habits and not a particular diet. Particular diets (for example, those with names attached to them such as the Atkins Diet, the Scarsdale diet, the Mediterranean Diet, etc.) can be hard to maintain because they often force the individual to eat foods that the individual may not particularly like. In particular, the Jupiter Scientific approach tries to maintain the same quantity of food consumed so that one is not hungry, but reduces the number of calories through changes in what one eats.
     As emphasized above, the only way to lose weight is to create a caloric deficit over a lengthy period of time. If this is to be accomplished through changes in eating habits then this means consuming less calories. The alternative approach of exercising more is not discussed here. However, including exercise in one's effort to lose weight is worth pursuing if one has the perseverance to do it.
     To create a caloric deficit, one should research the number of calories in the foods one is eating. Tables can be found in many places on the Internet. Below in the Appendix, we provide the calories of some foods. The results are given in calories per 100 grams because roughly the same weight of food “fills one up” by the same amount.footnote One then substitutes low-caloric foods for high-caloric foods, or one eliminates altogether or reduces the consumption of the latter.
     The following four methods create a caloric deficit without entailing a lot of hunger:
(i) Elimination of certain high-caloric foods: From the table below, one sees that nuts, seeds, bacon, potato chips, popcorn, french fries and fried foods in general, mayonnaise, candy, crackers, cookies should be eliminated from the diet or at least eaten infrequently and in very small quantities. For dieting purposes, crackers, cookies, nuts and seeds are bad snack foods.
(ii) Reduction in the consumption of high-caloric foods: One should eat less sweet deserts (cakes, pies, ice cream, etc.), eggs, bread, toast, soft and hard cheeses, and peanut butter, and use less sugar and drink less beer.
(iii) Substitution of lower-caloric foods for higher-caloric ones: The following replacements should be implemented:
   (a) sweet cereals → non-sweet cereals, or (even better) yogurt, instant oats or grits
   (b) butter and margarine → low-fat spreads
   (c) steak, ground beef, lamb, pork, and veal → chicken, turkey, lean steak, or non-fatty fish
   (d) fatty fish, oily fish or fried fish → non-fatty fish and shellfish
   (e) milk → skim milk
   (f) fruit juices and artificial fruit drinks → water, skim milk, tea, or coffee
   (g) soda → diet soda
(A major problem with fruit juices and non-diet soda is that they digest quickly like water so that they do not fill the stomach for long; yet unlike water they provide significant calories.)
(iv) Higher consumption of low-caloric foods: One should eat more vegetables and fresh fruits. Basically, one can eat as many vegetables as one wants because they are so low in calories. The same is almost true of fresh fruits. Instead of snacking on crackers and sweets, one should snack on foods such as carrots, celery, cucumbers, tomatoes, radishes, pre-cooked broccoli and cauliflower, apples, bananas, cantaloupe, watermelon, other melons, cherries, grapes, oranges, peaches, pears, and strawberries. Even sweet fruits such as cherries and strawberries are relatively low in calories (63 and 32 calories respectively per 100 grams). One should drink water more frequently because it fills the stomach creating a feeling of satiation and therefore a reduced desire for food, although the effect does not last long because water does not stay in the stomach very long.
     After using (i)-(iv), the person should approximately determine the numerical value of the caloric deficit in a day and, assuming that the person initially had a stable weight, use the following equation to compute the expected daily weight loss:

Weight loss per day (in grams) = (Daily caloric deficit)/9           (4)

Finally, one should regularly weigh oneself to confirm one's expectations based on Equation (4).
     After creating a caloric deficit, one needs to stick to it. It is better to lose weight slowly and steadily. Crash dieting often creates a very strong desire to eat, which can be difficult to resist, can be counterproductive and can be psychologically challenging. If one has a craving for food between meals, one should snack on raw vegetables and fresh fruits.
     It is important to be conscious of the calories in the foods that one is eating each day. A typical diet involves the daily intake of about 2000 calories for women and about 2600 for men; there are tables and calculators online indicating more precisely the desired caloric intake based on gender, height, age and activity level. A reasonable dieting goal is a reduction of 15%, or 300 calories for women and 400 calories for men per day translating into a weight loss of roughly one kilogram (about 2.2 pounds) per month or 12 kilograms (26 pounds) per year. For most people who want to lose a modest amount of weight, this approach allows one to achieve their goals in a year or less.
     To help with the dieting, one should also “let the stomach contract” somewhat. This means never eating or drinking so much that the stomach expands beyond what occurs when eating a moderate amount of food. The reason for doing this is given in the last paragraph in the section above entitled The Biology of Dieting.

Hypothetical and Real Examples of the Jupiter Scientific Approach to Weight Loss

Here we present the food adjustments of types (i)-(iv) for three examples. In addition to these food adjustments, the dieter should drink water more frequently and let the stomach “contract” as described above.

John A Doe

     John A is a person who likes desserts and snacks. In a typical day, he consumes 50 grams of crackers and cookies during non-meal times (~225 calories) and has ice cream, cake, or the equivalent for desert at dinner (~300 calories). Typically, he has cereal for breakfast (180 calories) with a glass of orange juice (115 calories). Other than these items, John A Doe's daily food regimen is reasonable.
     A simple weight reduction program is to replace the snacks (crackers and cookies) by fresh fruit and vegetables (a reduction of about 200 calories) and to cut the size of dinner desserts in half (a reduction of around 150 calories). John A should also eat more vegetables at dinner to compensate for eating less dessert. This program creates a daily caloric deficit of about 330. The expected weight loss is 0.08 pounds (37 grams) per day or 2.4 pounds (1.1 kilograms) per month. In a year, John A can expect to weigh 29 pounds (13 kilograms) less.
     If John A wanted to lose weight more rapidly, he could adjust his breakfast meal by selecting a lower caloric cereal containing 120 calories per serving, drinking half as much orange juice, and drinking some tea or coffee instead. This can create an additional deficit of 100 calories per day. He would then lose a little more than 3 pounds (1.4 kilograms) per month and almost 38 pounds (17 kilograms) per year. John A should follow the above food program until he achieves his desired weight and then he should continue some of the food changes to make sure that he does not “rebound.”

John B Doe

     John B Doe likes food. He likes pizza, french fries, fast-food hamburgers, fried onion rings, fried fish, bacon, eggs, et cetera. Of course, he doesn't eat all of these each day, but, on average, he eats something fried almost every day. John B needs to change his attitude toward food (from being something pleasurable to something that should contribute to better health) and to select different things to eat. Indeed, he needs to stop eating all the above-mentioned foods. For breakfast, he typically has coffee, orange juice, toast or muffins and sometimes eggs. As one might suspect, John B is badly overweight by 60 pounds.
     By eating the non-fried equivalent of the fried food, John B will reduce his daily caloric intake by about 100 calories. It turns out that John B can make the following additional adjustments using the suggestions in (iii) in the previous section: substitution of a low-fat spread for margarine (twice daily) (a reduction of 2 x 50 = 100 calories), cutting in half the size of desserts at lunch and dinner (a reduction 200 calories), and the elimination of (both natural and artificial) fruit juices (a reduction of 100 calories). For breakfast, John B should have coffee, toast/muffin (with low-fat spread) and fruit. John B should eat more fruit and vegetables (50 calories added to his diet) for lunch and dinner to make up for the reduction in deserts.
     With this program, John B can reduce his daily caloric intake by 450 calories, which means a daily weight loss of 50 grams or about one-ninth of a pound. In one month, he will lose 3.3 pounds (1.5 kilograms), and in one year 40 pounds (18 kilograms). John B will have to follow the above program for a year and a half to reach his targeted weight. A year and a half may seem like a long time, but it was during a 15-year period that John B put on all the extra weight.


     The following is a real-life example that illustrates the Jupiter Scientific Approach to Weight Reduction. Here is some background: Sam started a new office job. In the kitchen area at work, there were plenty of free drinks and food, including granola bars, other food snacks, and soda. Sam, who was extremely fit throughout his life and whose weight had been below average (body mass index of 22) and stable for more than 30 years, started to take advantage of the “freebies.” On average, each day, he drank a coke or other soda, and he also nibbled on the snacks. Six months into the job, he weighed himself and discovered his weight was 6 pounds (about 2.7 kilograms) above its previous stable value. At first, Sam thought it was just a fluctuation. However, during the next few weeks, he weighted himself, and, sure enough, he had gained 6 pounds.
     Sam was not so much concerned that he had gained 6 pounds but that he would continue gaining weight. So he decided to try the Jupiter Scientific approach. He switched to diet soft drinks and ceased eating snacks at work, he ate a little less at home, and he switched to a cereal with less calories. He told us that he was surprised at how long (2.5 months) it took his weight to return to its previous value. From the details of a conversation that we had with Sam, we estimate that he created a daily caloric deficit of about 325 calories. Equation (4) yields about 36 grams of body weight loss per day. To lose 2700 grams should then require 75 days or about 2.5 months, which was exactly how long it took!
     We can also use Equation (4) to see how small a caloric surplus was needed to create the 6 pound weight gain over six months: 6 pounds in 6 months is equivalent to 15 grams per day. Reversing Equation (4) gives a caloric surplus = 9 x15 or 135 calories per day.
     By the way, Sam did not have a weight rebound. Indeed, he continued drinking diet soda and eating a lower caloric cereal in the morning. However, he went back to eating his “regular amount” of food at home. Instead of rebounding, he told us that he actually continued losing weight and lost about 2 more pounds in the subsequent two months. At that point, he decided to increase the amount he was eating at meals and his weight stabilized increased and stabilized at its previous value.

Appendix: The Calories in Various Foods

To establish a daily caloric deficit, it is useful to know the calories contained in various foods and drinks. The following table provides some results for the approximate calories in 100 grams of food.

Food Calories per 100 grams

Oils and Spreads:
Vegetable oils ~850
Butter 750
Margarine 750
Low fat spreads 400

Seeds and Nuts:
Most nuts 550 to 700
Most seeds 550 to 600

Meats and Fish:
Bacon ~500
Most steak 200 to 275
Lean steak 150 to 200
Ground beef ~270
Lamb, pork, veal 250 to 400
Chicken, turkey 150 to 200
Other poultry (duck, goose, etc) 250 to 350
Non-fatty (not-fried) fish (cod, haddock, halibut, trout, tuna, canned tuna in water, etc) and (not-fried) shell fish (shrimp, clams, lobster, crab, etc) 100 to 150
Fatty or oily fish (mackerel, salmon, canned tuna in oil) 175 to 250
Fried fish 225

Breads ~250
Potatoes, Yams 100
Steamed rice 150
Boiled noodles and pasta 100 to 150
French fries 315

Most vegetables 10 to 40

Most (non-dried) fresh fruit 25 to 65
Dried fruits (dates, apricots, raisins) 250 to 325

Solid Dairy Products:
Yogurt (plain): ~70
Eggs 150 to 200
Ice cream 190 to 210
Frozen yogurt 130 to 160
Tofu 70

Processed foods examples:
Mayonnaise 700
Potato chips 525
Most crackers, cookies, candies, cakes, candy bars, chocolate 350 to 550
Most pies 225 to 300
Oiled-popped popcorn ~500
Cereals 350 to 450
Instant oats or grits cooked with water 60 to 70
Most soft cheeses 250 to 400
Cottage cheese 100
Most hard cheeses 250 to 450
Peanut butter 585
Jams and jellies 275
Ketchup 100
Mustard 70
Soups 70 to 160 per cup (8 ounces)

Sugar 390
Honey 275

Meatless spaghetti sauce ~50
Barbecue sauce ~150
Sweet and sour sauce ~150
Hot sauce 10
Teriyaki sauce 90
Tomato puree 40

Salad dressings 30 to 80 per tablespoon
Reduced-fat salad dressings 10 to 30 per tablespoon

Whole milk 60
Skimmed milk 35
Most sodas (non-diet) 120 to 180 (per 12 ounce can)
Diet sodas 0 to 10 per (12 ounce can)
Fruit juices 100 to 130 per cup (8 ounces)
Artificial fruit drinks 80 to 140 per cup (8 ounces)
Water 0
Tea and coffee (without milk or sugar) 1 per cup (8 ounces)
Wine 90 (5 ounces)
Beer 170 per half liter

Many sources went into the construction of the above table. One source Calorie King is fairly comprehensive and worth using.

A comment: If bread is used in a sandwich, it contributed moderately to the caloric content of a meal because it does not weigh too much: two slices are about 55 grams. The same is true for sauces and jams if used in moderation. Cereal is not quite as bad as it seems because most cereals are light and people typically eat 30 to 50 grams for breakfast.

Footnote: Volume of food is not relevant because it is compacted in the stomach.

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